[GiNaC-list] multi index storage of expressions

Charlls Quarra charlls_quarra at yahoo.com.ar
Tue Feb 20 20:40:31 CET 2007

--- Chris Dams <Chris.Dams at mi.infn.it> escribió:

> Why don't you simply invent a nice name for your
> multi-index object (say 
> "M") and store the values of them in an exmap. As in
> exmap m;
> m[indexed(M, idx(1,3), idx(2,3), idx(3,3))] =
> value_of_entry_1_2_3;
> After you have filled your exmap with all the
> indices you like, you can 
> use the exmap in a call to .subs to replace tensor
> objects with numerical 
> indices bij the appropriate value.

Thats a great way to do it when the object is quite
sparse, i'll keep that way in mind for special cases,
> Does this help?

it did. Thanks


Preguntá. Respondé. Descubrí. 
Todo lo que querías saber, y lo que ni imaginabas, 
está en Yahoo! Respuestas (Beta). 
¡Probalo ya! 

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